Obesity,Health at Every Size,and Public Health Policy

Obesity is associated with chronic diseases that may negatively affect individuals’ health and the sustainability of the health care system. Despite increasing emphasis on obesity as a major health care issue, little progress has been made in its treatment or prevention. Individual approaches to obesity treatment, largely composed of weight-loss dieting, have not proven effective. Little direct evidence supports the notion of reforms to the “obesogenic environment.” Both these individualistic and environmental approaches to obesity have important limitations and ethical implications. The low levels of success associated with these approaches may necessitate a new non–weight-centric public health strategy. Evidence is accumulating that a weight-neutral, nutrition- and physical activity–based, Health at Every Size (HAES) approach may be a promising chronic disease-prevention strategy.Obesity is defined as having a body mass index (BMI; defined as weight in kilograms divided by the square of height in meters) in excess of 30. Obesity is associated with numerous chronic health conditions, including diabetes, hypertension, heart disease, and certain cancers.1 The directionality of such associations is largely unknown, confounding may be present, and causality has only definitely been assigned to obesity with respect to osteoarthritis and ovarian cancer.2 Despite these limitations, to counter the health effects of obesity-associated conditions, individuals frequently are encouraged to lose weight to improve individual and population health. However, diet-induced weight loss stimulates somatic and psychological ‘homeostatic pressures’ that induce weight regain.3 These mechanisms include hormonal alterations, reduced satiety and energy expenditure, and increased hunger.3,4 These adaptations stimulate weight regain in more than 90% of weight losers.5,6 In acknowledgment of the limited effectiveness of individual approaches to weight loss, increasing emphasis has been placed on environmental reforms. However, when weight loss is the key motivator of such changes, they are hindered by a limited evidence base and ethical difficulties. These concerns suggest public health would benefit from a shift in focus from weight loss to disease prevention for individuals of all ages and sizes, with a focus on health rather than weight-loss outcomes, and environmental reforms devoted to enhancing livability, accessibility, and equity. Evidence is accumulating that a weight-neutral, nutrition- and physical activity–based, Health at Every Size (HAES) approach may be a promising chronic-disease prevention, and overall well-being, strategy.